A liquid crystal display panel is sealed after it is completed, so that a driving voltage of liquid crystal can be measured only by indirect methods. One of the measuring methods is to measure optical quantum, such as measuring brightness to obtain a light transmittance, so as to obtain a voltage according to the corresponding relationship between the voltage and the optical quantum. For example, it can be speculated according to the relationship between the voltage and the light transmittance.
It can be seen that in the conventional measuring method, the driving voltage of liquid crystal cannot be directly measured and the driving voltage of liquid crystal cannot be monitored in real time when the liquid crystal display panel is in operation, so that the measured driving voltage of liquid crystal is incorrect, and some problems in the liquid crystal display panel cannot be correctly solved.
Accordingly, it is necessary to provide a measuring method to solve the technical problem in the prior art.